NATO’s Secretary Gral. Jens Stoltenberg said Thursday that Moscow’s growing military presence in the Baltic skies is “unjustified” and that Russian military aircraft regularly fail to file flight plans or communicate with Baltic air controllers, and fly with their transponders off posing a risk to civil aviation.

Visiting the Amari air base in Estonia, Mr. Stoltenbergsaid NATO´s air fighters have intercepted planes more than 100 times in the Baltic region during 2014, a threefold increase compared to 2013.

NATO Chief said the alliance “should stay vigilant” because during 2014 Russia increased its military air presence in the Norwegian Sea, Black Sea as well as the Baltic area, but most flights occurred in international airspace.

Mr. Stoltenberg said NATO aircraft have conducted 400 intercepts to protect the airspace of European alliance members, an increase of 50 percent from 2013.